Hong Kong skies get clean report card

Air pollution in Hong Kong, which touts itself as Asia’s World City, not only affects locals but also makes it less attractive to expatriates, eroding its claim to global relevance, research has shown.

Human resources consultancy ECA International ranked Hong Kong last month as the 28th most livable city in Asia for expats, out of more than 480 locations. Its longterm rival, Singapore, was in first place.

The report was based on multiple factors, including climate, housing and utilities, but pointed out that air quality and pollution were holding Hong Kong back from climbing the ladder.

Smog has plagued the city for a long time. In 2013, Hong Kong’s Environment Bureau released a clean air plan with concrete goals and action plans to tackle the problem, including lowering levels of nitrogen dioxide and large particulate matter, known as PM10, by 40 percent by 2020.

A progress report released by the government covering the first five years of the plan showed roadside air pollution, usually more severe than in general residential or commercial areas, had been reduced by the end of 2016, with nitrogen dioxide concentrations down by 31 percent from 2012 levels and PM10 down by 28 percent.

The main reason for the improvement was the government’s move in 2013 to phase out the city’s most polluting vehicles — some 82,000 older diesel commercial vehicles.

The plan is to remove all pre-Euro IV diesel vehicles by next year, with the government setting aside HK$10 billion ($1.27 billion) for subsidies to encourage owners to replace polluting old diesel vehicles with cleaner new ones.

Vehicles complying with the latest standard, Euro VI, release far lower levels of nitrogen oxides and particulate matter than those meeting the previous Euro IV and Euro V standards.

In the meantime, newly registered diesel vehicles have, since February 2014, been limited to a service life of just 15 years, after which the government will not renew their license.

Inadequately maintained liquefied petroleum gas and petrol vehicles, and Euro II and Euro III compliant franchised buses are other major sources of roadside air pollution that are also on the government’s radar.

As in the rest of the world, Hong Kong is moving toward the use of electric buses, and the government has arranged for the city’s franchised bus companies to test e-buses. Five single-decked, battery-driven e-buses and two super-capacitor buses were being tested on the city’s roads in the first quarter of last year.

However, Hong Kong’s hilly terrain, high humidity and heavy summer rain pose a challenge to the new technology.

Meanwhile, in August, Shenzhen in Guangdong province became the first city in the world to convert its entire bus fleet to e-buses.